Intermediate mass fragment emission in heavy-ion collisions: Energy and system mass dependence

Abstract

Emission of intermediate mass fragments (IMFs) $(Z>~3)$ from central collisions of ${}^{40}\mathrm{Ar}{+}^{45}\mathrm{Sc}\mathrm{} (E/A=35--115 \mathrm{MeV}),$ ${}^{58}\mathrm{Ni}{+}^{58}\mathrm{Ni} (E/A=35--105 \mathrm{MeV}),$ and ${}^{86}\mathrm{Kr}{+}^{93}\mathrm{Nb} (E/A=35--95 \mathrm{MeV})$ was studied. For each system, the average number of IMFs per event increased with beam energy, reached a maximum, and then decreased. The beam energy of peak IMF production increased linearly with the combined mass of the system. The number of IMFs emitted at the peak also increased with the system mass. Percolation calculations showed a weaker dependence of the peak beam energy and the number of IMFs on the total mass of the system.